Pipe coupling

Abstract

A pipe coupling comprises a pair of flanges adapted to be secured together in face to face relation to form a fluid-tight coupling. Each flange incorporates at least one coding device formed to provide a key and a keyway, which coding devices are so disposed and arranged on the flanges that the two flanges can only be secured together to form the fluid-tight coupling if the coding devices on the respective flanges correspond with one another, and each of the pair of coding devices comprising, secured within a hole in a flange, a bar member whose cross section is partly cut away to provide the keyway and key, and the bar member being secured in the hole in one of a predetermined number of relative orientations, selectively achieved by adjusting, by rotation, the bar member in the hole.

I claim: 
     
       1. A pipe coupling comprising a pair of flanges adapted to be secured together in face to face relation to form a fluid-tight coupling, wherein each said flange includes at least one coding device formed to provide a key and a key-way, which coding devices are so disposed and arranged on said flanges that the two flanges can only be secured together to form a said fluid-tight coupling if the coding devices on the respective flanges correspond with one another, and wherein each of a pair of said coding devices comprises a hole defined in a said flange, and a bar member secured within said hole in one of a predetermined number of relative orientations, selectively achieved by adjusting, by rotation, the bar in said hole, and wherein said bar member is partly cut away along its transverse cross-section with said cut away extending into said hole to thereby provide a said key-way and key. 
     
     
       2. A pipe coupling of the kind in which a fluid-tight coupling is made by securing together in proper mating relationship a pair of opposed flanges, the coupling being equipped with a security arrangement whereby only a pair of flanges which are intended to be coupled, can be properly coupled, whereas a pair of flanges not intended to be coupled, are incapable of being properly coupled, wherein said coupling with its security arrangement comprising in combination: (i) a coding device provided with each of the flanges of said pair of opposed flanges, said coding device including a pair of holes each formed in a respective flange and being in axial alignment when the coupling is properly made, and a bar member disposed in each of the holes;   (ii) each bar member being shaped to define, by reduction of its transverse cross-section, a portion which protrudes from its flange hole to define a key and a cut-back portion which defines a recess in the flange hole;   (iii) said protruding portion of each bar member being received, as a key and key-way fit, in the recess defined by the cut-back portion of its opposing bar member, and vice versa, said pair of bar members being in key and key-way mating register when the coupling is properly made; and wherein   (iv) each of the bar members of the matable pair is adjustable, by rotation in its hole, into a selected one of at least two alternative dispositions, with said pair of bar members being capable of being brought into key and key-way mating register, to allow the coupling to be properly made, only when the bar members have been adjusted, by rotation in their holes, such that, when the flanges are disposed face to face just prior to coupling, one bar member has its protruding portion disposed offset by 180° relative to the disposition of the protruding portion of the other bar member with which it is matable, in key and keyway fashion, when the coupling is properly made.   
     
     
       3. A coupling according to claim 1 or claim 2, wherein each of said flanges to be coupled includes at least two said coding devices each consisting of a bar member (5) disposed in a hole in a flange. 
     
     
       4. A coupling according to claim 1 or claim 2, wherein each bar member has a head portion which is of a predetermined shape which is a keying fit in a correspondingly shaped recess in one end of a flange hole, the head portion being fittable in said shaped recess in a flange hole in one of a predetermined number of relative orientations. 
     
     
       5. A coupling according to claim 4, wherein said predetermined shape is one of triangular, rectangular, pentagonal, hexagonal or octagonal. 
     
     
       6. A coupling according to claim 4, wherein said predetermined shape has a non-circular curved periphery. 
     
     
       7. A coupling according to claim 6, wherein said predetermined shape is one of oval, oblong, and foliant shape. 
     
     
       8. A coupling according to claim 7, wherein said predetermined shape is a foliant shape selected from one of clover-leaf, trefoil and quatrifoil shapes. 
     
     
       9. A coupling according to claim 1 or claim 2, and including a masking plate secured to a said flange and locking a bar member in place in a flange hole, such that adjustment, by rotation of said bar member in its hole, cannot be accomplished until said masking plate is removed. 
     
     
       10. A coupling according to claim 1 or claim 2, wherein, said bar member includes a head portion, and wherein   said coding device further includes, a housing integral with the flange in which the bar member is mounted, and   a spring loaded plunger movable within said housing and engageable behind said head portion of the bar member for securing each bar member in its flange hole.     
     
     
       11. A coupling according to claim 10, wherein said bar member includes a stem which is of reduced cross-sectional size as compared with the head portion of the bar member, said plunger bearing against said stem such that adjustment, by rotation of the bar member in its hole, cannot be accomplished until the plunger is moved from engagement behind the head portion of the bar member.